At its inception, TSR sold its products directly to customers, shipped to game shops and hobby stores, and wholesaled only to three distributors which were manufacturers of miniatures figurines.[3] In 1975, TSR picked up one or two regular distributors.[3] In 1976, TSR joined the Hobby Industry Association of America and began exhibiting at their annual trade show, and began to establish a regular network of distributors.[3]

Tim Kask was hired in 1975 as TSR's first Publications Editor, and the company's first full-time employee.[4] When Don Kaye died of a stroke in 1975, the Tactical Study Rules partnership was dissolved.[5]

Brian Blume and Gary Gygax, the remaining owners, incorporated a new company, TSR Hobbies, Inc.,[5] of which Blume and his father, Melvin Blume, had the larger share. The former assets of the partnership were transferred to TSR Hobbies, Inc. Empire of the Petal Throne became the first game product published under TSR Hobbies, followed by two supplements to the D&D game, Greyhawk and Blackmoor.[5] Also released in 1975 were the board game Dungeon! and the Wild West RPG Boot Hill.[5] TSR began hosting the Gen Con Game Fair in 1976, and featured the first-ever D&D open tournament that year.[5][6]D&D supplments Eldritch Wizardry and Gods, Demi-gods & Heroes were released in 1976, and the original D&D Basic Set was released in 1977.[5] Also in 1977 TSR Hobbies published the original Monster Manual, the first hardbound book ever published by a game company, and the following year the Advanced Dungeons & Dragons game was released, with its first product being the Player's Handbook, followed by a series of six adventure modules that had previously only been used in tournaments.[5] Also in 1978, TSR Hobbies moved out of Gygax's home and into downtown Lake Geneva above the Dungeon Hobby Shop.[5] In 1979, the Dungeon Master's Guide was published, and radio ads featuring "Morley the Wizard" were broadcast.[5]

Gygax granted exclusive rights to Games Workshop to distribute TSR products in the UK, after meeting with Ian Livingstone and Steve Jackson.[3] Games Workshop printed some original material and also printed their own versions of various D&D and AD&D titles, in order to avoid high import costs.[3] When TSR could not reach an agreement with Games Workshop regarding a possible merger, TSR created a subsidiary operation in the UK.[3] To meet growing international demand, the company TSR, Ltd. was formed in England in 1980.[5] Gygax hired Don Turnbull to head up the operation, which would also extend into continental Europe during the 1980s.[3] TSR, UK. produced and the U and UK series of AD&D modules and B/X1 and X8 for basic D&D,[3] as well as the original Fiend Folio. TSR, UK also produced Imagine magazine for 31 issues.[3]

The first campaign setting for the AD&D game, the World of Greyhawk, was introduced in 1980. The Top Secret espionage role-playing game was introduced in 1980; reportedly, a note written on TSR stationery about a fictitious assassination plot, as part of playtesting the new game, brought the FBI to TSR's offices. That same year, the Role Playing Game Association was formed to promote quality roleplaying and to unite gamers around the country.[5] In 1981, Inc. magazine listed TSR Hobbies as one of the hundred fastest-growing privately held companies in the US. That same year, TSR Hobbies moved offices again to a former medical supply building with an attached warehouse; in 1982, TSR Hobbies broke the 20-million mark in sales.[5]

In 1982, TSR Hobbies decided to terminate the license to Grenadier Miniatures and started producing its own AD&D miniatures line, and then a line of toys, while licensing part of the AD&D toy line to LJN.[3] Also in 1982, TSR introduced two new roleplaying games, Gangbusters and Star Frontiers. Exclusive distribution of the D&D game was established in 22 countries, with the game being translated first into French, followed by many other languages including Danish, Finnish, German, Hebrew, Italian, Japanese, Korean, Norwegian, and Swedish. In 1982, an Educational department was established to develop curriculum programs for reading, math, history, and problem solving, with the most successful program being the Endless Quest book series.[5]

Ownership of Melvin Blume's shares were later transferred to Kevin Blume. With the board of directors consisting of Kevin and Brian Blume plus Gygax, Gygax was primarily a figurehead president & CEO of the corporation with Brian Blume as President of creative affairs and Kevin as President, operations effect in 1981. TSR Hobbies sought diversification, acquiring or starting several new business ventures; these include a needlecraft business, miniatures manufacturing, toy and gift ventures, and an Entertainment division to pursue motion picture and television opportunities.[5] The company also acquired the trademarks and copyrights of SPI and Amazing Stories magazine.[5] In 1983, the company was split into four companies, TSR, Inc. (primary successor), TSR International, TSR Ventures and TSR Entertainment, Inc.[2]

Gygax left for Hollywood to found TSR Entertainment, Inc. (later Dungeons & Dragons Entertainment Corp.), which attempted to license D&D products to movie and television executives. His work would eventually lead to only a single license for what later became the Dungeons & Dragons cartoon.[7] However, the series spawned more than 100 different licenses, and led its time slot for two years.[5] The Blumes were forced to leave the company after being accused of misusing corporate funds and accumulating large debts in the pursuit of acquisitions such as latchhook rug kits that were thought to be too broadly targeted.[8] Within a year of the ascension of the Blumes, the company was forced to post a net loss of 1.5 million US dollars, resulting in layoffs for approximately 75% of the staff. Some of these staff members went on to form other prominent game companies such as Pacesetter Games, Mayfair Games and to work with Coleco's video game division.

TSR, Inc., released the Dragonlance saga in 1984 after two years of development, making TSR the number one publisher of fantasy and science fiction novels in the USA.[5]Dragonlance consisted of an entirely new game world promoted both by a series of game supplements and a trilogy of novels written by Margaret Weis and Tracy Hickman. "The Dragons of Autumn Twilight", the first novel in the series, reached the top of the New York Times Best Seller list, encouraging TSR to a launch a long series of paperback novels based on the various official settings for D&D.

Gygax, who at that time owned only approximately 30% of the stock, requested that the Board of Directors remove the Blumes as a way of restoring financial health to the company. In an act many saw as retaliation, the Blumes sold their stock to Lorraine Williams.[8] Gygax tried to have the sale declared illegal; after that failed, Gygax sold his remaining stock to Williams and used the capital to form New Infinity Productions.

Williams was a financial planner who saw the potential for transforming the debt-plagued company into a highly profitable one. However, she was disdainful of the gaming field, viewing herself as superior to gamers.[9][10] Williams implemented an internal policy under which playing games was forbidden at the company. This resulted in many products being released without being playtested (some were playtested "on the sly") and a large number of products being released that were incompatible with the existing game system.

TSR released the Forgotten Realms campaign setting in 1987. That same year, a small team of designers began work on the second edition of the AD&D game. In 1988, TSR released a Bullwinkle & Rocky roleplaying game, complete with a spinner and hand puppets. That same year, TSR released a wargame based on Tom Clancy's novel, The Hunt for Red October, which became one of the biggest selling wargames of all time. The Gen Con Game Fair joins forces with its major competitor, Origins. In 1989, the Advanced Dungeons & Dragons 2nd Edition is released, with a new Dungeon Master's Guide, Player's Handbook, the first three volumes of the new Monstrous Compendium, The Complete Fighter's Handbook, The Complete Thief's Handbook, and a new campaign setting, Spelljammer, all released in the same year. Also in 1989, the RPGA Network branched out into additional countries, including Norway, Sweden, Denmark, the U.K., Israel, and Australia.[5]

Through Williams' direction, TSR solidified its expansion into other fields, such as magazines, paperback fiction, and comic books. Through her family, Williams personally held the rights to the Buck Rogers license and encouraged TSR to produce Buck Rogers games and novels. TSR would end up publishing a board game and a role-playing game, the latter based on the AD&D 2nd Edition rules.[8]

In 1990, the Ravenloft setting was released, and Count Strahd von Zarovich soon became one of the most popular and enduring villains. The West Coast division of TSR was opened in order to develop various entertainment projects, including a series of science fiction, horror, and action/adventure comic books. In 1991, TSR released the Dark Sun campaign setting, as well as an introductory Dungeons & Dragons game aimed at beginners. TSR also released the first set of three annual sets of collector cards in 1991. In 1992, TSR released the Al-Qadim setting. TSR's first hardcover novel, Legacy by R. A. Salvatore was released in that year, and climbed to the top of the New York Times bestseller list within weeks. In 1992, the Gen Con Game Fair broke all previous attendance records - for any U.S. gaming convention - with more than 18,000 people in attendance. In 1993, the DragonStrike Entertainment product is released as a new approach to gaining new players, including a 30-minute video which explains the concepts of role-playing. 1994 saw the release of the Planescape campaign setting.[5]

By the early 1990s, the profits from TSR's fiction department actually far surpassed that of their gaming publications. During the height of its success, TSR made an annual profit of over one million U.S. dollars, and maintained a staff of 400 employees.

However, problems grew in the company's business practices. After the emergence of collectible card games, TSR released several new collectable game lines: Dragon Dice and Spellfire. Neither found great success in the market place. Their inventory control became virtually nonexistent, and their warehouse became packed full of unsellable product. At the same time, TSR began retaliating against fan fiction and other creative work derived from TSR intellectual property, which angered many long-time customers and fans. Other new entrants into the RPG genre introduced competing fantasy worlds, which fragmented the RPG community, further reducing TSR's already wilting consumer base. TSR itself introduced no fewer than six campaign settings over the 1990s (Al-Qadim, Birthright, Council of Wyrms, Dark Sun, Planescape and Ravenloft, in addition to the traditional five settings of Mystara, Dragonlance, Forgotten Realms, Greyhawk and Spelljammer), diluting its own fan base and creating competition between its expensive boxed campaign sets. Some campaign boxed sets (particularly Planescape) actually sold for less money than they cost to make. These and other factors, such as a disastrous year for its fiction lines in 1996 (over one million copies of tie-in books for various game lines were returned to TSR that year), led to TSR ending accumulating over $30 million in debt by 1996, and having to endure multiple rounds of layoffs.[10]

Ryan Dancey, Vice President of Wizards of the Coast, believed that TSR failed before of "...a near total inability to listen to its customers, hear what they were saying, and make changes to make those customers happy."[11]

With the decline of TSR, Wizards of the Coast, publishers of the collectible card game Magic: The Gathering, became the largest role-playing game company. Wizards of the Coast purchased TSR and its intellectual properties in 1997,[6] ending the company's slow fall from grace.[12] TSR employees were given the opportunity to transfer to Wizards of the Coast's offices in Washington; some accepted the offer. Corporate offices in the Lake Geneva office were closed. Over the next few years, various parts of the company were resold to other companies, while in 1999, Wizards of the Coast was itself purchased by Hasbro, Inc. In 2002 Gen Con was sold to Peter Adkison's Gen Con, LLC.[13] Also in 2002 TSR's magazines were transferred to Paizo Publishing.[14] The TSR brand name continued for several years, then was retired. Soon after, TSR trademarks were allowed to expire.

In 1984, TSR started publishing novels based on their games. Most D&Dcampaign settings had their own novel line, the most successful of which were the Dragonlance and Forgotten Realms lines with dozens of novels released in each.

TSR published quite a number of fantasy and science fiction novels unconnected with their gaming products, such as L. Dean James' "Red Kings of Wynnamyr" novels, Sorcerer's Stone (1991) and Kingslayer (1992); Mary H. Herbert's five "Gabria" novels (Valorian, Dark Horse, Lightning's Daughter, City of the Sorcerers and Winged Magic); and also humorous fantasy fiction including Roy V. Young's "Count Yor" novels Captains Outrageous (1994) and Yor's Revenge(1995). However such projects never represented more than a fraction of the company's fiction output, which retained a strong emphasis on game-derived works.

After its initial success faded, the company turned to legal defenses of what it regarded as its intellectual property. In addition, there were several legal cases brought regarding who had invented what within the company and the division of royalties, including several lawsuits against Gygax.[15] These actions reached their nadir when the company threatened to sue individuals supplying game material on Internet sites. In the mid-1990s, this led to frequent use of the nickname "T$R" in discussions on RPG-related Internet mailing lists and Usenet, as the company was widely perceived as attacking its customers. Increasing product proliferation did not help matters; many of the product lines overlapped and were separated by what seemed like minor points (even the classic troika of Greyhawk, the Forgotten Realms and Dragonlance suffered in this regard).

The company was the subject of an urban myth stating that it tried to trademark the term "Nazi". This was based on a supplement for the Indiana Jones RPG in which some figures were marked with "NaziTM". This notation was in compliance with the list of trademarked character names supplied by Lucasfilm's legal department.[16] Later references to the error would forget its origin and slowly morph into stories of TSR's trying to register such a trademark, possibly aided by TSR's own reputation late in its existence as a "trademark Nazi" company.